It is known to place a small gold ingot of between 1 and 10 grammes in a cavity made in the body of a plastic card. In a first variant the card body has a through aperture the profile of which substantially fits that of the ingot. In another variant, the dimensions of the through aperture are larger than those of the ingot. Two transparent plastic sheets are laminated respectively on the two surfaces of the pierced card body. The ingot is thus confined between the two plastic sheets. To hold the ingot in a substantially central position in the aperture, a flange or raised portion forming a frame is provided on one or both plastic sheets. The frame is obtained for example by thermoforming. It may also be affixed to one or both of the plastic sheets. This frame surrounds the ingot so that the latter remains in a substantially central position in the aperture. In particular, the two plastic sheets are welded together along the frame so as to form a closed pouch for the ingot. A transparent peripheral area is therefore obtained around the ingot. However, the thick frame inside the aperture is visible and unattractive. Although transparent, the frame causes a visual deformation and prevents the side surface of the ingot from being properly seen. Moreover, the two plastic sheets can easily be deformed in the aperture area at the periphery of the transparent frame. In this area, and in the pouch where the ingot is located, air is generally trapped between the two plastic sheets. The card is not, therefore, compact and it is possible for the ingot to be handled such that it moves out of the plane of the card body. Consequently, the card can easily be damaged and is of limited longevity.